1. Field of the Invention
The invention relates to a hydrogen operated power system, and more particularly, to a hydrogen operated power system that uses a supply system to supply a gaseous fuel from a fuel supply tank to a hydrogen operated power system.
2. Description of the Related Art
As one kind of hydrogen operated power system, technology has been proposed which, in a fuel cell system, both circulates hydrogen supplied from a fuel supply system to a fuel cell via a hydrogen circulation path, and circulates oxygen supplied from an oxidizing agent supply system to the fuel cell via an oxidizing agent circulation path (JP-A-7-240220). This system aims to improve the utilization ratio of hydrogen and oxygen supplied from the fuel supply system and the oxidizing agent supply system by circulating the hydrogen and oxygen that was not consumed in the fuel cell using the circulation paths.
This kind of a hydrogen operated power system uses a circulation pump driven by a motor to circulate the hydrogen and oxygen. A rotational position sensor, such as a resolver, is typically used in driving control of the motor to accurately detect the rotational position of the motor. However, when a rotational position sensor is used for driving control of a motor that is used with a hydrogen circulation pump, the sensor may deteriorate due to hydrogen embrittlement or the like such that it is unable to control the driving of the motor, which may interfere with the operation of the system.